diff --git a/src/libraries/System.Security.Cryptography.Pkcs/pkg/System.Security.Cryptography.Pkcs.pkgproj b/src/libraries/System.Security.Cryptography.Pkcs/pkg/System.Security.Cryptography.Pkcs.pkgproj
index 1acbfcd5f63c50..740607c0579164 100644
--- a/src/libraries/System.Security.Cryptography.Pkcs/pkg/System.Security.Cryptography.Pkcs.pkgproj
+++ b/src/libraries/System.Security.Cryptography.Pkcs/pkg/System.Security.Cryptography.Pkcs.pkgproj
@@ -2,18 +2,15 @@
   <Import Project="$([MSBuild]::GetPathOfFileAbove(Directory.Build.props))" />
   <ItemGroup>
     <ProjectReference Include="..\ref\System.Security.Cryptography.Pkcs.csproj">
-      <SupportedFramework>net461;netcoreapp3.0</SupportedFramework>
+      <SupportedFramework>net461;netcoreapp2.0;uap10.0.16299;$(AllXamarinFrameworks)</SupportedFramework>
     </ProjectReference>
     <ProjectReference Include="..\src\System.Security.Cryptography.Pkcs.csproj" />
-    <HarvestIncludePaths Include="ref/net46;lib/net46;runtimes/win/lib/net46" />
-    <HarvestIncludePaths Include="ref/netstandard1.3;runtimes/win/lib/netstandard1.3;lib/netstandard1.3" />
-    <HarvestIncludePaths Include="ref/netstandard2.0" />
-    <HarvestIncludePaths Include="ref/netcoreapp2.1;lib/netcoreapp2.1;runtimes/win/lib/netcoreapp2.1" />
-    <!--
-      Suppress NETStandard.Library collpasing as it add more dependencies then needed in some
-      scenarios like .NET Framework which adds an unecessary amount of package dependencies to download
-    -->
-    <SuppressMetaPackage Include="NETStandard.Library" />
+    <PackageFile Include="buildTransitive\System.Security.Cryptography.Pkcs.targets"
+                 TargetPath="buildTransitive\netcoreapp2.0" />
+    <File Include="$(PlaceholderFile)"
+          TargetPath="buildTransitive\netcoreapp3.0" />
+    <!-- Exclude TFMs that aren't supported by the package anymore from validation. -->
+    <ExcludeHarvestedSupportedFramework Include="netcoreapp1.0;netcoreapp1.1;netcore50;uap10.0;net46" />
   </ItemGroup>
   <Import Project="$([MSBuild]::GetPathOfFileAbove(Directory.Build.targets))" />
 </Project>
diff --git a/src/libraries/System.Security.Cryptography.Pkcs/pkg/buildTransitive/System.Security.Cryptography.Pkcs.targets b/src/libraries/System.Security.Cryptography.Pkcs/pkg/buildTransitive/System.Security.Cryptography.Pkcs.targets
new file mode 100644
index 00000000000000..e293d8184ea105
--- /dev/null
+++ b/src/libraries/System.Security.Cryptography.Pkcs/pkg/buildTransitive/System.Security.Cryptography.Pkcs.targets
@@ -0,0 +1,6 @@
+<Project InitialTargets="_ErrorForSystemSecurityCryptographyPkcsOnNetCoreApp20">
+  <Target Name="_ErrorForSystemSecurityCryptographyPkcsOnNetCoreApp20"
+          Condition="'$(SuppressTfmSupportBuildWarnings)' == ''">
+    <Error Text="System.Security.Cryptography.Pkcs doesn't support netcoreapp2.0. Consider updating your TargetFramework to netcoreapp3.1 or later." />
+  </Target>
+</Project>
diff --git a/src/libraries/System.Security.Cryptography.Pkcs/ref/System.Security.Cryptography.Pkcs.csproj b/src/libraries/System.Security.Cryptography.Pkcs/ref/System.Security.Cryptography.Pkcs.csproj
index 5b42437c4fab14..f3079cd3ff753a 100644
--- a/src/libraries/System.Security.Cryptography.Pkcs/ref/System.Security.Cryptography.Pkcs.csproj
+++ b/src/libraries/System.Security.Cryptography.Pkcs/ref/System.Security.Cryptography.Pkcs.csproj
@@ -1,20 +1,18 @@
 <Project Sdk="Microsoft.NET.Sdk">
   <PropertyGroup>
-    <TargetFrameworks>$(NetCoreAppCurrent);netcoreapp3.0;netstandard2.1;net461</TargetFrameworks>
+    <TargetFrameworks>$(NetCoreAppCurrent);netcoreapp3.0;netstandard2.1;netstandard2.0;net461</TargetFrameworks>
     <ExcludeCurrentNetCoreAppFromPackage>true</ExcludeCurrentNetCoreAppFromPackage>
     <Nullable>enable</Nullable>
   </PropertyGroup>
   <!-- DesignTimeBuild requires all the TargetFramework Derived Properties to not be present in the first property group. -->
   <PropertyGroup>
-    <IsPartialFacadeAssembly Condition="$(TargetFramework.StartsWith('net4'))">true</IsPartialFacadeAssembly>
-    <!-- Currently the netstandard build is locked to the net472 API -->
-    <AssemblyVersion Condition="$(TargetFramework.StartsWith('netstandard'))">4.0.4.0</AssemblyVersion>    
+    <IsPartialFacadeAssembly Condition="'$(TargetFramework)' == 'net461'">true</IsPartialFacadeAssembly>
   </PropertyGroup>
   <ItemGroup>
     <Compile Include="System.Security.Cryptography.Pkcs.cs" />
-    <Compile Include="System.Security.Cryptography.Pkcs.netcoreapp.cs" Condition="!$(TargetFramework.StartsWith('net4'))" />
+    <Compile Include="System.Security.Cryptography.Pkcs.netcoreapp.cs" Condition="'$(TargetFramework)' != 'net461' and '$(TargetFramework)' != 'netstandard2.0'" />
   </ItemGroup>
-  <ItemGroup Condition="$(TargetFramework.StartsWith('net4'))">
+  <ItemGroup Condition="'$(TargetFramework)' == 'net461'">
     <Reference Include="System.Security" />
   </ItemGroup>
   <ItemGroup Condition="'$(TargetFramework)' == '$(NetCoreAppCurrent)'">
diff --git a/src/libraries/System.Security.Cryptography.Pkcs/src/System.Security.Cryptography.Pkcs.csproj b/src/libraries/System.Security.Cryptography.Pkcs/src/System.Security.Cryptography.Pkcs.csproj
index 71a20f021ca9c4..3f947a6f44e3bc 100644
--- a/src/libraries/System.Security.Cryptography.Pkcs/src/System.Security.Cryptography.Pkcs.csproj
+++ b/src/libraries/System.Security.Cryptography.Pkcs/src/System.Security.Cryptography.Pkcs.csproj
@@ -1,7 +1,6 @@
 <Project Sdk="Microsoft.NET.Sdk">
   <PropertyGroup>
     <AllowUnsafeBlocks>true</AllowUnsafeBlocks>
-    <UsePackageTargetRuntimeDefaults Condition="'$(IsPartialFacadeAssembly)' != 'true'">true</UsePackageTargetRuntimeDefaults>
     <IncludeDllSafeSearchPathAttribute>true</IncludeDllSafeSearchPathAttribute>
     <NoWarn>$(NoWarn);CA5384</NoWarn>
     <Nullable>enable</Nullable>
@@ -12,8 +11,7 @@
   <PropertyGroup>
     <IsPartialFacadeAssembly Condition="$(TargetFramework.StartsWith('net4'))">true</IsPartialFacadeAssembly>
     <OmitResources Condition="$(TargetFramework.StartsWith('net4'))">true</OmitResources>
-    <!-- Currently the netstandard build is locked to the net472 API -->
-    <AssemblyVersion Condition="$(TargetFramework.StartsWith('netstandard'))">4.0.4.0</AssemblyVersion>
+    <UsePackageTargetRuntimeDefaults Condition="'$(IsPartialFacadeAssembly)' != 'true'">true</UsePackageTargetRuntimeDefaults>
   </PropertyGroup>
   <Import Project="$(CommonPath)System\Security\Cryptography\Asn1\AsnXml.targets" Condition="'$(IsPartialFacadeAssembly)' != 'true'" />
   <Import Project="$(CommonPath)System\Security\Cryptography\Asn1Reader\System.Security.Cryptography.Asn1Reader.Shared.projitems" Condition="'$(IsPartialFacadeAssembly)' != 'true'" />
@@ -640,9 +638,6 @@
     <PackageReference Include="System.Buffers"  Version="$(SystemBuffersVersion)" />
     <PackageReference Include="System.Memory" Version="$(SystemMemoryVersion)" />
     <ProjectReference Include="$(LibrariesProjectRoot)System.Runtime.CompilerServices.Unsafe\src\System.Runtime.CompilerServices.Unsafe.ilproj" />
-    <!-- Ref assembly for netstandard2.0 isn't live built anymore. -->
-    <PackageDownload Include="$(MSBuildProjectName)" Version="[$(SystemSecurityCryptographyPkcsVersion)]" />
-    <ResolvedMatchingContract Include="$(NuGetPackageRoot)$(MSBuildProjectName.ToLowerInvariant())\$(SystemSecurityCryptographyPkcsVersion)\ref\$(TargetFramework)\$(MSBuildProjectName).dll" />
   </ItemGroup>
   <ItemGroup Condition="!$(TargetFramework.StartsWith('$(NetCoreAppCurrent)'))">
     <PackageReference Include="System.Security.Cryptography.Cng" Version="$(SystemSecurityCryptographyCngVersion)" />